Firearm with firing pin retarding means



Oct. 24, .1967 E. MUHLEMANN 3,348,453

FIREARM WITH FIRING PIN RETARDING MEANS Filed MaICh 7, 1966 Fig. [-Y

2 Sheets-Sheet 1 l Oct. 24, 1967 E. MUHLEMANN 3,348,453

FIREARM WITH FIRING PIN RETARDING MEANS Filed March 7, 1966 2 Sheets-Sheet 2 as 215 5.3 IQ# 195. 51

x 3,3! go 2 -1 l United States Patent O 3,348,453 FIREARM WITH FIRING PIN RETARDING MEANS Ernst Muhlemann, Zurich, Switzerland, assignor to Oerlikon-Buhrle Holding A.G., Zurich, Switzerland Filed Mar. 7, 1966, Ser. No. 532,384 Claims priority, application Switzerland, Mar. 10, 1965, 3,337/ 65 7 Claims. (Cl. 89-180) ABSTRACT OF THE DISCLOSURE An automatic rearm having a breech housing with a breech block locked to the housing in the igniting position, and a tiring pin control member for controlling the locking of the breech block, the control member being adapted to slide relative to the block out of a position of abutment on ignition. A- friction brake means is provided between the control member and either the breech housing or breech block, the friction brake means comprising a spring-loaded movable friction element engageable in the abutment position within a catch or notch. The friction brake means controls the rebounding of the control member to such an extent that the friction element is permitted to automatically disengage without permitting the breech head to become unlocked.

The invention relates to an automatic firearm in which the breech housing has a breech head or block which is locked to the housing in the igniting position, and a control member for controlling the locking of the breech head, the control member being adapted to slide relatively to the head out of a position of abutment on ignition.

Known weapons of this type have the disadvantage that the control member rebounds from the breech head, leading to premature unlocking of the breech head. This is particularly dangerous in the case of a hang-tire cartridge.

The invention is characterized in that a friction brake is provided between the control member and one of the two portions formed by the breech housing and the breech head, that thefriction brake has a spring loaded, movable friction element which engages in the abutment position in a catch provided with a friction surface, and that the friction' brake prevents the control member from rebounding from the breech head to such an extent that the friction element is automatically disengaged without the breech head being unlocked.

Weapons of other types are known in which the control member is prevented from rebounding by locking it to the breech head. This however involves using an additional movable breech member for controlling the locking.

Three examples of the invention are illustrated in the drawings, in which:

- FIGURE 1 is a diagrammatic view of an axial longitu-dinal section, taken along the line I--I in FIGURE 3, through part of a rearm with the breech element in the locked position.

FIGURE 2` is a similar view showing the breech element in the unlocked position.

FIGURE 3 is a section taken along the line III-III in FIGURE 1.

FIGURE 4 is a section taken along the line IV--IV in FIGURE 3.

FIGURE 5 is a section taken along the line V--V in FIGURE 1 showing a first embodiment of the friction brake.

FIGURE 6 is a section along the line VI-VI in FIGURE 5.

FIGURE 7 is a section along the line VII-VII in FIGURE 5.

FIGURE 8 is a section along the line VIII-VIII in KURE 1 showing a second embodiment of the friction ra e.

FIGURE 9 is a section along the line VIII- VIII in FIGURE 1 showing a third embodiment of the friction brake.

In FIGURES 1 and 2 the breech head of a two-part breech element is shown at 1 and the control member at 2. The control member 2, which is inserted in a recess 107 in the breech head 1 as shown in FIGURES 3 and 4 and which is movable in this recess, has a driving connection with two coupling members 26. The -coupling members 26 are each movably housed in a chamber formed by a web 108 of the head 1 and a side wall of the housing 3 and engage in recesses in the control member 2 by means of projections 109. Sleeves 5 carry cams 24 which give them a driving connection with the two coupling members 26, the cams 24 passing through slots in the side walls j of the breech housing 3 and engaging in recesses in the coupling members 26. The sleeves 5, movably mounted in supports 4, are subjected to the pressure of closing springs 6 (FIGURES 5 and 6) provided in them and bearing on the rear ends of the supports 4 (not shown). The supports 4 have extensions or attachments 25 pivotally mounted on bolts 23 which are provided on straps 22 fixed to the breech housing 3. Two bolt locks 7 (FIG- URES 1 and 2) are pivotally mounted on the breech head 1 with engaging surfaces 8 provided on the housing 3 to support them. A- bushing 9 (FIGURES 5, 6 and 7) directed transversely to the axis of the sleeves 5 is fixed in each side of the housing 3. A friction element 10 is disposed within each bushing 9 and is subjected to the pressure of a spring 11 movably mounted in it.

As shown in FIGURES 5, 6 and 7, the circular end face of the bushing 9 projecting from the housing 3 contains a slot-like aperture 91 extending parallel with the axis of the sleeve 5. The extension 101 of the friction element 10, which has two surfaces 102, 103 also parallel to said axis, projects through this aperture and extends further out through an aperture 41 in the support 4 into a slot 51 forming a catch in the sleeve 5. The extension 101 of the element 10 has two end faces inclined to the axis of the weapon, the front one 104 extending more steeply in relation to this axis than the rear one 105. The front end 53 of the slot 51 in the sleeve 5 is in the same direcf tion as the steeper surface 104 of the friction element 10'.

Axially of the weapon, the distance that the control member 2 has to cover backwards to force the connecting element 10 out of the catch 51 is shorter than the distance that the control member 2 has to cover in order to unlock the breech head 1 when a shot has been fired.

On the basis of this construction the first embodiment (FIGURES l to 7) operates as follows:

For the advance of the breech element 1, 2 into the igniting position (FIGURE l) by the action of closing springs 6, once the breech head 1 has reached its foremost position in which it is in contact with the breech housing 3 at the point 12, the control member 2 moves on and guides the lbolt locks 7 outward so that these bear on the surfaces 8 of the breech housing 3 and prevent the breech head 1 from moving backward. The member 2 then takes control of (subordinates) the bolt locks 7 and prevents them from leaving the locked position. On reaching the foremost position, the tiring pin 21, joined to the member 2, ignites the cartridge 13.

Before the breech head 1 reaches its foremost position the edges 52 of the front ends of the sleeves 5 run onto the surfaces 105 of friction elements 10 and press them inward. On account of the slight inclination of the surfaces 105 in relation to the axis of the sleeve 5 the friction between the surface 105 and the edge of the sleeve 5 striking it is only slight and has no effect on the movement of the sleeve. During the further forward movement of the sleeves 5 the friction elements 10 bear on the outer surfaces of the sleeves 5. When the control member 2, which is joined to the sleeves 5, reaches its foremost position (the ignition position) and strikes the breech head 1, the extensions 101 of the friction elements 10' drop into the slots 51 in sleeves 5 under the pressure of springs 11. This happens so quickly that the surfaces 104 of the friction elements engage the friction surfaces 53 bounding the slots before the control member 2 rebounds from the igniting position, and when it does rebound the friction elements 10 are overridden by the outer surfaces of the sleeves 5 and so the elements 10 cannot come into action.

During the rebounding action the surface 53 of the sleeve 5 strikes the surface 104 of friction element 10 and presses the latter abruptly inward, overcoming the force of spring 11, so that the sleeve 5 can now move backward across the friction element 10. The weight of the latter, the return spring 11 and the inclination of surface 104 are adjusted so that during this process of guiding in the friction element 10, the control mem-ber 2 transmits its kinetic energy acquired on the rebound to breech housing 3 by friction and retreats from the igniting position only far enough to disengage the friction element 10 without terminating the subordination of the bolt locks 7.

Further backward movement of the control member 2 into the FIGURE 2 position, in which the bolt locks 7 are no longer subordinated and are swung inward from the locked position, takes place by means of unbolting bars 14. The bars are moved in a manner which is known but not illustrated by the pressure of gases diverted (branched) from the barrel 15 of the gun and act through incisions in the front end walls of the supports 4 on the front ends of the sleeves 5 and through these on the control member 2. By pivoting the supports 4 about the bolts 23 in the direction of the arrow (FIGURE l) the cams 24 on both sleeves 5 are brought out of engagement with the control member 2 of the breech element. As the friction elements 10 are now eliminated, the breech element can then be unlocked and removed from the housing 3 without any special exertion by pulling back the control member 2.

FIGURE 8 shows a second embodiment of the invention as used with a breech element according to FIGURES 1 and 2. The main difference from the first example is that here the friction element is arranged in the control member 2 and acts on the breech head 1.

The cylindrical friction element 16 is movably mounted in a bore 17 perpendicular to the direction in which the control member 2 moves. The front part of friction element 16 has a milled portion or cutout 161 parallel with its axis; this is engaged by a pin 19 xed in the control member 2 so as to prevent the friction element 16 from dropping out when the weapon is dismantled.

A recess or catch 20 is worked into the breech head 1; this forms part of a sphere with a radius slightly larger than that of the spherical end 163 of friction element 16. The depth of the catch 20 is such that no sticking occurs between it and the friction element 16 when the control member 2 rebounds.

This construction results in a mode of operation similar to that in the first example:

When the control member 2 strikes the breech head 1 before ignition the friction element 16 springs into the catch 20 under the pressure of spring 18. When control member 2 rebounds, the friction element 16 rubs against the friction surface of catch 20, cancelling out the rebound energy of control member 2, and is disengaged from the catch 20` without unlocking the breech.

FIGURE 9 shows a third embodiment which is also used in one of the breech elements illustrated in FIG- URE 1.

The friction element comprises a pawl 27 placed in a recess 30 in control member 2. A biased spring 34 bearing on the bottom of the bore 31 in the control member projects into a cutout 28 in pawl 27. The breech head 1 has a catch 29 into which the friction element 27 springs when the control member 2 reaches the abutment position during its forward movement. The recess or catch 29 has a friction surface 32 in the same direction as the end face 33 of pawl 27.

The third embodiment (FIGURE 9) operates similarly to the second example:

When the control mem-ber 2 strikes the breech head 1 before ignition the pawl 27 springs into the catch 29, and when it rebounds the rebound energy is cancelled out by friction between the pawl surface 33 and the surface 32. It is also contemplated that the catch may be provided in the control member and the friction element on the breech head or breech housing.

Although particular preferred embodiments of the invention have been disclosed above for illustrative purposes, it will be understood that variations or modifications thereof lying within the scope of the appended claims are fully contemplated.

The embodiments of the invention in which an exclusive property or privilege is claimed are defined as follows:

1. An automatic firearm comprising: a breech housing having a chamber; a breech head arranged in said housing and adapted to be locked to said housing in the igniting position;

control means for controlling the locking of the breech head in the housing, said control means being relatively movable with respect to said breech head from a position of abutment in which ignition takes place; and

friction brake means coacting with said control means for frictionally braking the movement of the control means away from said position of abutment, said friction brake means comprising means defining a catch recess provided with a friction surface and a spring-loaded, slideable friction element stationary with respect to said housing at least as long as the breech head is locked in said igniting position, said friction element being slideably movable in a direction transverse to the direction of movement of the control means and adapted to be received into said catch recess when the control means is in the position of abutment.

2. An automatic firearm according to claim 1, wherein said friction brake means coact between said breech housing and said control means with said catch recess being formed on one of said Ibreech housing and control means and the friction element being slideably mounted in the other of said breech housing and control means.

3. An automatic firearm according to claim 2, wherein the friction element comprises a cylindrical body slideably mounted in said breech housing.

4. An automatic firearm according to claim 1, wherein said friction brake means coacts between said control means and said breech head with said catch recess being formed in one of said control means and breech head and the friction element being slideably received in the other said control means and breech head.

5. An automatic firearm according to claim 4, wherein the control means is provided with a recess therein, said friction element being slideably mounted therein.

6. An automatic firearm comprising:

a breech housing having a chamber;

a breech head provided in said chamber and adapted to be locked to said housing in the igniting position;

a control member for controlling the locking of the breech head in the housing, said control member being relatively movable with respect to said breech head from a position of abutment in which ignition takes place;

friction brake means for braking the movement of the control member from said position of abutment, said friction brake means comprising a catch provided with a friction surface and a spring-loaded, movable friction element which engages said catch when the control member is in said abutment position;

said friction element comprising a cylindrical element radially slideably received in said control member and having a rounded end portion extending beyond the periphery of the control member and including a spring disposed in said control member for urging said friction element outwardly therefrom;

said catch comprising a semispherical depression in said breech head disposed in the path of movement described by said friction element during movement of the control member with respect to said breech head, the radius of said depression being larger than that of said rounded end portion so as to frictionally impede -but not prevent movement of said rounded end portion outwardly therefrom;

whereby the friction brake prevents said control member from moving from said breech head to such an extent that said friction element is automatically disengaged from said catch without said breech head being unlocked.

'7. An automatic firearm comprising:

a breech housing having a chamber;

a breech head provided in said chamber and adapted to be locked to said housing in the igniting position;

a control member for controlling the locking of the -breech head in the housing, said control member being relatively movable with respect to said breech head from a position of abutment in which ignition takes place;

friction brake means for braking the movement of the control member from said position of abutment, said friction brake means comprising a catch provided with a friction surface and a spring-loaded, movable 5 friction element which engages said catch when the control member is in said abutment position; slide means mounted for reciprocation along said breech housing and fixed to said control member for movement therewith at least during the initial portion of its movement out of abutment with said breech head, said catch being provided on said slide means; said friction element being recessed in said breech housing and including spring means for urging said friction element outwardly from said housing into contact with said slide means for engagement with said catch; whereby the friction brake means prevents said control member from movement from said breech head to such an extent that said friction element is automatically disengaged from said catch without said breech head being unlocked.

References Cited UNITED STATES PATENTS 1/1960 Hoyt 89--190 X 5/1966 Maillard 89-190 

1. AN AUTOMATIC FIREARM COMPRISING: A BREECH HOUSING HAVING A CHAMBER; A BREECH HEAD ARRANGED IN SAID HOUSING AND ADAPTED TO BE LOCKED TO SAID HOUSING IN THE IGNITING POSITION; CONTROL MEANS FOR CONTROLLING THE LOCKING OF THE BREECH HEAD IN THE HOUSING, SAID CONTROL MEANS BEING RELATIVELY MOVABLE WITH RESPECT TO SAID BREECH HEAD FROM A POSITION OF ABUTMENT IN WHICH IGNITION TAKES PLACE; AND FRICTION BRAKE MEANS COACTING WITH SAID CONTROL MEANS FOR FRICTIONALLY BRAKING THE MOVEMENT OF THE CONTROL MEANS AWAY FROM SAID POSITION OF ABUTMENT, SAID FRICTION BRAKE MEANS COMPRISING MEANS DEFINING A CATCH BRAKE MEANS COMPRISING MEANS DEFINING A SPRING-LOADED, SLIDEABLE FRICTION ELEMENT STATIONARY WITH RESPECT TO SAID HOUSING AT LEAST AS LONG AS THE BREECH HEAD IS LOCKED IN SAID IGNITION POSITION, SAID FRICTION ELEMENT BEING SLIDEABLY MOVABLE IN A DIRECTION TRANSVERSE TO THE DIRECTION OF MOVEMENT OF THE CONTROL MEANS AND ADAPTED TO BE RECEIVED INTO SAID CATCH RECESS WHEN THE CONTROL MEANS IS IN THE POSITION OF ABUTMENT. 